"Watch what happens with the Programme Motion. ...If one isn't tabled at all, it means the Whips believe they wouldn't have won one - at least now. They may wait and table one later, after Tory MPs are growing tired of interminable debate on the bill. But watch for a blame game to begin if the motion falls or is delayed. (By the way, keep an eye out for Labour pro-reform diehards voting for the Programme.) The Whips may timetable debate for weekends. They will threaten to make the House sit during the summer recess. Most likely, they will make it sit late on a Thursday, wrecking backbenchers' constituency diaries for the next day, and causing them deliberate local embarrassment by doing so. The aim of such manoevres is to make backbench MPs blame the rebels for forcing extra sittings on the Government. The response of the rebels will be to move closure motions to make it clear that they're not to blame."

Paul Waugh on Politics Home (£) now writes that the Programme motion has indeed been withdrawn. Three quick points.

As I wrote this morning, it was evident from yesterday's debate that the tide was with the rebels. Conservative MPs will increasingly have been unsure what David Cameron and the whips really wanted them to do had there been a vote. As I pointed out this morning, the best way of helping Mr Cameron would have been to vote against the programme, and James Forsyth reports that there seems to have been a move among Tory MPs precisely to this end.

The withdrawal of the programme motion is bad for the Government's authority in general, and therefore for Mr Cameron - and, especially, for Nick Clegg.

However, the aim of the Liberal Democrats, as described above, will be to see Mr Cameron and the Tory Whips make life so difficult for their backbenchers by timetabling debate through nights or at weekends that the latter fold and eventually vote for a programme motion. As I say above, the "Sensibles" will now be preparing their own tactics - including the use of closure motions.

The Bill will get its Second Reading later today, since Labour will vote for it. We will provide a list of Tory rebels as soon as we can.

And then off it trundles into the wilderness of untimetabled debate...

1.45pm Update Conor Burns said on the Politics Show earlier this afternoon that some of the names of signatories have been withheld. No doubt they will be issued in due course - all part of the chess game with the Whips and, more particularly, Downing Street over the bill.

The letter apparently says that the bill "threatens to pile a constitutional crisis on top of an economic crisis", and has been sent to all Conservative MPs. It is part of the tactical chess game that I wrote about earlier this morning.

The Whips will find it hard to get MPs who've signed a letter opposing the programme motion to support it, but some slippage must be assumed. However, there will be some bill opponents who haven't signed the letter.

So all in all, I will be surprised in the event of a programme motion being tabled if the number of rebels is below 50. The figure that the lobby will be watching out for is 82 - one more than the big revolt over an EU referendum last year.

And the number of signatories must less likely that a programme motion is tabled at all.

As well as Sir Malcolm, there are two other former senior Ministers: Peter Lilley and David Davis.

Members of the new intake include Nadhim Zahawi, Rory Stewart, Andrew Griffiths, Jesse Norman, Simon Hart and George Eustice.

The letter says:

“The Lords Bill is a measure of profound constitutional significance... It threatens to pile a constitutional crisis on top of an economic crisis.

“Specifically what is now proposed will undermine the primacy of the Commons, with competing chambers which will lead to legislative gridlock. It will create hundreds of unaccountable new elected politicians at a time when we as a party are committed to reducing the cost of politics an; gd it will produce a chamber which is less expert, less diverse and significantly more expensive than the present one.

“The commitments in our 2010 election manifesto and in the Programme for government - to seek consensus and to bring forward proposals - have been fulfilled. We hope you will support us in giving this Bill the full and unrestricted scrutiny it deserves.”